Guaifenesin Oral Solution
» Guaifenesin Oral Solution contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of guaifenesin (C10H14O4).
Packaging and storage— Preserve in tight containers.
USP Reference standards 11
USP Guaifenesin RS Click to View Structure
Identification— The retention time of the guaifenesin peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
Uniformity of dosage units 905
for oral solution packaged in single-unit containers: meets the requirements.
Deliverable volume 698
for oral solution packaged in multiple-unit containers: meets the requirements.
pH 791: between 2.3 and 3.0.
Alcohol content, Method I 611 (if present): between 90.0% and 115.0% of the labeled amount of C2H5OH.
Assay—
Mobile phase, Benzoic acid solution, Resolution solution, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Guaifenesin Tablets.
Assay preparation— Transfer an accurately measured volume of Oral Solution, equivalent to about 200 mg of guaifenesin, to a 100-mL volumetric flask, dilute with water to volume, and mix. Transfer 2.0 mL of this solution to a 100-mL volumetric flask, add 45 mL of methanol, dilute with water to volume, and mix.
Procedure— Proceed as directed in the Assay under Guaifenesin Tablets. Calculate the quantity, in mg, of guaifenesin (C10H14O4) in each mL of the Oral Solution taken by the formula:
5C/V(rU / rS)
in which V is the volume, in mL, of Oral Solution taken; and the other terms are as defined therein.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Clydewyn M. Anthony, Ph.D.
Senior Scientific Liaison
1-301-816-8139
(SM22010) Monographs - Small Molecules 2
Reference Standards RS Technical Services
1-301-816-8129
rstech@usp.org
USP35–NF30 Page 3382
Pharmacopeial Forum: Volume No. 30(1) Page 107